Pitman-krotectob fob habvesting-mackines



M. A. JOHNSON.

PITMAN PROTECTOR FOR HARVESTING MACHINES.

APPLICATION FILED MAY 5. 1919.

1,335,897, Patented Apr. 6, 1920.

MELVIN A. JOHNSON, OE TENS TRIKE, MINNESOTA.

PITMAN-PROTECTOR FOR HARVESTING-MACHINES.

Specification of Letters Patent.

Patented Apr. 6, 1920.

Application filed May 5, 1919. Serial No. 295,013.

To all whom it may concern:

Be it known that I, MELVIN A. JoHNsoN, a citizen of the United States,residing at Tenstrike, in the county of Beltrami and State of Minnesota,have invented a new and useful Pitman-Protector for Harvesting-Machines, of which the following is a specification.

My invention relates to improvements in harvesting machines of the kindshaving a sickle-bar operated by a pitman, like mowers, reapers andself-binders. The main object of the invention is to provide suchmachine with an efficient guard to protect the pitman from gettingbroken, the way it frequently happens in ordinary harvesters, by eitherdriving the machine forward with the pitman against stumps, stones andother obstructions, or by letting the pitman in its vibratory movementbreak over the top of such obstructions.

In the accompanying drawing,-

Figure 1 is a partly completed top view of a mower equipped with mypitman protector. Fig. 2 is a section on the line 22 in Fig. 1.

Referring to the drawing by reference numerals, 3 designates the groundwheels, 4: the axle, 5 the main frame, 6 the pole and 7 the seat of anordinary mowing machine, some parts of which are omitted in the drawingbecause they do not involve my invention.

The usual forwardly extending arm 8 of the frame 5 has its extreme frontend pivotally secured at 9 to a transverse frame bar 10, which isscrewed into the part 10*. Upon the other end of the bar is secured at11 the usual upwardly arched portion 12 of the shoe 13, in which thefinger bar 14 is pivoted at 15. The bar 10 is bent at 16 to form adiagonal frame bar, 10*, whose rearward end is secured at 17 underneaththe main frame 5.

The sickle-bar 18 is connected by a pitman 19 to a crank wheel 20, whoseshaft 21 is journaled in the arm 8 and frame 5 and provided with a bevelpinion 22, which is ber slidably keyed on the short shaft 21 and adaptedto engage clutch teeth 28 on the gear 23 when the latter is to run thecrank shaft and the pitman. The member 27 is shifted by a lever (notshown).

The pitman protector comprises a strong strip 29 of sheet metal forminga kind of angle iron or channel along the under side and front side ofthe pitman. Said protector strip or plate is held in place between theground and the pitman by clevises 30 taken over the bar 10 and securedby bolts 31 to the inclined front portion 29 of the protector. The rearportion or 29 is secured to the frame by rearwardly and upwardlyextending braces 32 and 33; the latter brace is preferably secured tothe bar 10 by a clip or U-bolt 34;.

In Fig. 1 35 shows a clearance in the base of the protector for thelower end of the pitman. Near said clearance the front cornor of theguard has an upstanding finger, 36, engaging either the front side ofthe bar 10, as in Fig. 2, or it may bear against the front side of aprojection 37 of the frame portion known as the shoe, 13, according asthe structure of the machine may vary.

In Fig. 2 it will be easiest understood that when the machine is inoperation and is moving forward and a stump, as 38, or other obstructionconcealed in the grass or grain is encountered, the pitman will getbroken either by being forced against the side of the obstruction or bybeing vibrated downward upon the top of it under the rapid action of thecrank 20; but when protected by my device the inclined portion 29 of thesame will act as a broad runner and by gliding over the obstruction willlift the machine with'the pitman safely over and past the obstructionand then let it down again. The guard is also slightly curved upward atits rear edge, as at 29 in Fig. 2, so as to slide over minorobstructions in case the machine be moved backward.

What I claim is:

1. In a harvesting machine, a main frame having a bar extendingdiagonally rearwardly from the shoe of the machine to a point of theframe near the main axle of the machine, and mounted in the frame, atransversely disposed cutter bar, a transversely arranged pitman, acrank operating the pitman, a guardmg plate extending all alongunderneath said crank and pitman, and rear- Wardly'direcced bracessecuring said guarding plate to said diagonal bar and to the main frame;said guarding plate having its front portion inclined upwardly.

2. The structure specified in clainnl, said guarding plate forming achannel along the greater portion of the pitman.

3. The structure specified in claim 1, said guarding plate havingat oneend a clearance 10 for the lower end of the; pitman.

4c. The structure specified in claim 1, said guarding plate having alsoits rearward edge curved or inclined partly upward.

Intestimony whereof I affix' my signa" 15 ture.

MELVIN A. JOHNSON.

